Speaking to news.com.au from her hometown of Wollongong in NSW on Friday, Holtznagel laughed when asked about how Molloy's comments made her feel.

"I thought it was hilarious. Like seriously, if I'm going to take modelling career advice or any advice on fitness, he's not going to be the person I take it from," she said.

"I did see that he's now gone on a health kick. Apparently he's been so fat shamed since saying that about me that he is now going on a diet. Now I guess you know how it feels."

Holtznagel is not yet a household name like fellow Aussies Elyse Knowles or Jesinta Franklin, but she's been working consistently as a model for the past 10 years.

"I would love to do Sports Illustrated [magazine]. That's my goal," she said.

In 2011 at age 17, she was named runner-up of Australia's Next Top Model and developed a close relationship with the late Charlotte Dawson, who was one of the judges on the show and took her own life in 2014.

Holtznagel was dropped by a modelling agency for being "too commercial" - fashion industry code for "lose a few kilos" - but she's turned her healthy curves into a long term career.

"I am naturally tall and have a small frame. But I love going to the gym. I feel well when I have that routine, when I get up and go to the gym and go to work," she said.

"If there is a day where I'm like 'I don't want to go to the gym', I just remember how good I'll feel afterwards. Even if you just do 40 minutes, you always feel so much better afterwards so I always try to do something.

"But you still want to have fun and enjoy yourself and have a glass of wine. Can you imagine how miserable you would be if you couldn't do anything like that?"

Simone Holtznagel on the cover of US Playboy. Picture: Supplied

She's currently enjoying a career high as the face of Bras N Things, with her incredible figure plasted over the chain's store fronts around the country.

"Yesterday I came home from the airport and went to the shops to get a few things and I went into Bras and Things and saw the pictures. It's weird, but I guess it's pretty cool.

"I remember first seeing my Guess billboard in LA [she is an ambassador for the brand].

Simone modelling for a Guess campaign. Picture: Tatiana Gerusova.

"I got out of the car and this guy was looking at me weirdly. He looked at the billboard, looked back at me and he said 'Is that you?'. And I was like 'Yeah mate' and he said 'Congratulations that's awesome'," she recalled.

"At first I was kind of embarrassed. It was on Sunset Boulevard at this big intersection I was like 'Oh my god this is so embarrassing', but then I was like 'Actually, f**k it, that's me on a billboard. I'm going to take some pictures. I don't care if people think I'm weird'."